Radiator with thin fins

ABSTRACT

A radiator with thin fins. The method includes steps of forming a plurality of thin fins and spacers by punching metal sheets of high coefficient of heat transmission into predetermined shapes, spacing said thin fins alternately with said spacers and binding them into an assembly with a plurality of rivets extended through holes separately formed near lower end at predetermined positions, and grinding a bottom of the assembly to remove unevenness thereof. The radiator manufactured in this method may include increased number of fins within a limited area to create largely increased contact surfaces with air and thereby enables quick radiation of heat produced by, for example, chips associated with the radiator. A fan may be mounted to a top of the radiator to enhance the radiating effect.

[0001] (This is a divisional application of applicant's U.S. patentapplication Ser. No. 09644522 filed on Aug. 21, 2000)

BACKGROUND OF THE INVENTION

[0002] The present invention relates to a radiator with thin fins. Themethod includes steps of forming thin fins and spacers with metal sheetshaving high coefficient of heat transmission, spacing the finsalternately with the spacers and riveting them together to form anassembly, and grinding a bottom of the assembly to remove unevennessthereof. The radiator so produced includes a plurality of thin finswithin a reduced area to create largely increased contact surface withair and thereby enables quick radiation of heat.

[0003] It is known that a chip 1 (see FIG. 9) used, for example, in acomputer would produce large amount of heat when it operates. To radiatethe large amount of heat produced by the chip 1 to maintain normaloperation of the chip 1, it is a common practice to associate a radiatorwith the chip 1. Conventionally, such radiator is formed from extrudedaluminum. FIG. 1 illustrates an example of such conventional radiator20. As can be seen from FIG. 1, the radiator 20 mainly includes a flatbase 201 and a plurality of radiating ribs 202 vertically extended fromand parallelly spaced on a top of the base 201. The radiator 20 isassociated with the chip 1 by flatly attaching the base 201 to a top ofthe chip 1, so that heat produced by the chip 1 during operation thereofis absorbed by the base 201 and quickly transmitted to the a pluralityof ribs 202. The ribs 202 provide large contacting surfaces with air toenable quick and continuous radiating of heat into the air via thesurfaces of the ribs 202, so that the chip 1 is able to continue normaloperation thereof without the risk of having a rising temperature.

[0004] As mentioned above, the radiator 20 is formed from aluminumextrusion. The ribs 202 on the top of the base 201 have a thickness thatis restricted by the die through which aluminum material is extruded toform the radiator. It is currently impossible to make the ribs 202 ofthe extruded aluminum radiator 20 to have a very small thickness toincrease the number of ribs 202 that may be provided on the base 201.The radiator 20 therefore provides only limited surfaces for contactingwith air. This fact also inevitably causes the radiator 20 to have onlylimited radiating performance. Moreover, when the radiator 20 is to beused on a large heat-producing area, it is necessary to cut new dieshaving increased dimensions in order to extrude more aluminum materialto form an enlarged radiator 20. The cost for cutting the new and largedies would adversely increase the cost of the radiator 20.

[0005] It is therefore desirable to develop a radiator that eliminatesthe drawbacks existing in the conventional ribbed radiator formed fromextruded aluminum.

SUMMARY OF THE INVENTION

[0006] A primary object of the present invention is to provide aradiator having a plurality of thin fins and therefore providing largelyincreased contacting surface with air to enable accelerated radiating ofheat.

[0007] Another object of the present invention is to provide radiatorthat has a plurality of thin fins and can be used with a radiator fan toachieve enhanced radiating effect.

[0008] The radiator with thin fins is manufactured in the followingsteps: forming a plurality of thin fins and spacers by punching metalsheets of high coefficient of heat transmission into predeterminedshapes, spacing said thin fins alternately with said spacers and bindingthem into an assembly with a plurality of rivets extended through holesseparately formed near lower end at predetermined positions, andgrinding a bottom of the assembly to remove unevenness thereof.

[0009] The radiator manufactured in this method may include increasednumber of fins within a limited area to create largely increased contactsurface with air and thereby enables quick radiation of heat producedby, for example, a chip associated with the radiator.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The structure and the technical means adopted by the presentinvention to achieve the above and other objects can be best understoodby referring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein

[0011]FIG. 1 is a perspective of a conventional ribbed radiator;

[0012]FIG. 2 is a flow chart showing steps of producing the radiatorwith thin fins according to the present invention;

[0013]FIG. 3 is an exploded perspective of the radiator with thin finsaccording to the present invention;

[0014]FIG. 4 is a fragmentary, assembled side view of the radiator ofFIG. 3 before being ground to remove unevenness at a bottom thereof;

[0015]FIG. 5 is an assembled perspective of the radiator of the presentinvention;

[0016]FIG. 6 schematically shows the manner of riveting the thin fins ofthe radiator together;

[0017]FIG. 7 is a graph in which two curves separately show theradiating effects achieved by the radiator of the present invention andthe conventional ribbed radiator formed from extruded aluminum;

[0018]FIG. 8 is an assembled side view showing the radiator of thepresent invention being associated with a chip; and

[0019]FIG. 9 is an exploded perspective showing the radiator of thepresent invention works with a radiator fan to enhance the radiatingeffect thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Please refer to FIG. 3 that is an exploded perspective of afinned radiator 2 according to the present invention for associatingwith a chip 1 (see FIGS. 8 and 9) to radiate heat produced by the chip 1during operation thereof. As shown, the finned radiator 2 mainlyincludes a plurality of thin fins 21, a plurality of spacers 22, and aplurality of rivets 23. FIG. 2 is a flow chart of a method formanufacturing the finned radiator 2. As shown, the method includes thefollow steps:

[0021] 1. Forming the thin fins 21:

[0022] The thin fins 21 are formed by punching metal sheets having highcoefficient of heat transmission into a desired flat and straight shapeby using a die designed for this purpose, such that each of the thinfins 21 has a plurality of through holes 211 formed near a lower end atpredetermined positions. The thin fins 21 may have dimensions dependingon actual needs.

[0023] 2. Forming the spacers 22:

[0024] The spacers 22 are also formed by punching metal sheets havinghigh coefficient of heat transmission into a desired flat and straightshape by using a die designed for this purpose, such that each of thespacers 22 has a plurality of through holes 221 formed at predeterminedpositions corresponding to the through holes 211 on the thin fins 21.The formed spacers 22 are transversely extended long plates and have aheight lower than that of the thin fins 21 and a thickness preferablylarger than that of the thin fins 21.

[0025] 3. Assembling the fins 21 and the spacers 22:

[0026] Assemble the thin fins 21 and the spacers 22 so that the thinfins 21 are spaced alternately with the spacers 22 and the through holes211 separately align with the through holes 221, and then bind theassembled thin fins 21 and spacers 22 together by sequentially extendingthe rivets 23 through the aligned through holes 211 and 221 to provide apreform of the radiator 2.

[0027] 4. Grinding and polishing:

[0028] When using the rivets 23 to rivet the fins 21 and the spacers 22together, clearances between the through holes 211, 221 and the rivets23 would possibly result in an uneven bottom of the preform of theradiator 2, as shown in FIG. 4. Use a suitable grinding tool to grindand smoothen the uneven bottom of the preform of the radiator 2 toprovide a finished radiator 2 as shown in FIG. 5.

[0029] In assembling the thin fins 21 and the spacers 22 in the abovestep 3, an auxiliary tool 3 is used to ensure accurate and stableassembling of the thin fins 21 and the spacers 22. As can be seen inFIG. 6, the auxiliary tool 3 includes a front portion formed of aplurality of forward extended and parallelly spaced projections. Thefront portion of the auxiliary tool 3 is adapted to insert into thepreliminarily assembled fins 21 and spacers 22 with the a plurality offorward projections separately located in a space defined between twoadjacent fins 21, so that the fins 21 spaced by the spacers 22 are wellsupported by the forward projections of the auxiliary tool 3. By thismanner, the fins 21 would not bias while the rivets 23 are extendedthrough the holes 211 and 221 to bind the fins 21 and the spacers 22together.

[0030] The metal sheets for producing the fins 21 and the spacers 22 maybe, for example, aluminum sheet and copper sheet that all have highcoefficient of heat transmission. Since the fins 21 have very smallthickness compared with the conventional extruded aluminum ribs, theremay be more fins 21 provided within a unit area to provide the radiator2 with increased contact surfaces with air to enable acceleratedradiating of heat produced by the chip 1. Experiments indicate theradiator 2 having thin fins 21 is more effective than the conventionalones in radiating heat. The experiment results are shown in FIG. 7 inwhich curve A indicates the temperature of a first chip 1 using theradiator 2 of the present invention, and curve B indicates thetemperature of a second chip 1 identical to the first chip 1 but using aconventional extruded aluminum radiator 20. As can be seen from thegraph of FIG. 7, the first and the second chips 1 that are tested at thesame time present quite different radiating behavior, wherein the firstchip 1 using the radiator 2 of the present invention has much lowertemperature than the second chip 1 after both of them have operated for20 minutes. This proves that the radiator 2 having thin fins 21according to the present invention is superior to the conventionalextruded aluminum radiator 20.

[0031] To further enhance the radiating effect of the radiator 2 withthin fins 21, a radiator fan 4 may be mounted to a top of the radiator2. To do so, two outmost fins 21′ of the assembled thin fins 21 areseparately provided at top edges with two spaced and outward extendedears 212 for the radiator fan 4 to fasten onto the ears 212, as shown inFIG. 9. The fan 4 and the radiator 2 could together more quickly radiateheat produced by the chip 1 and thereby effectively control thetemperature of the chip 1 and protect the same from rising temperature.

[0032] An important feature of the radiator 2 of the present inventionis that numbers of the thin fins 21 and the spacers 22 may becorrespondingly increased to provide a radiator 2 adapted to associatewith a large heat-producing area. In other words, the radiator 2 is notrestricted to any particular dimensions. And, there is no need to makedifferent dies for manufacturing the fins 21 and the spacers 22 ofdifferent sizes, and cost for such dies could be saved, accordingly.

What is claimed is:
 1. A radiator with thin fins, comprising a pluralityof thin fins, a plurality of spacers, and a plurality of rivets; saidthin fins being made of metal sheets having high coefficient of heattransmission and being formed by punching said metal sheets with diesdesigned for such purpose, said thin fins being flat and straight andhaving a plurality of first through holes formed near a lower end atpredetermined positions; said spacers being made of metal sheets havinghigh coefficient of heat transmission and being formed by punching saidmetal sheets with dies designed for such purpose, said spacers beingflat and straight and having a plurality of second through holes formednear a lower end at predetermined positions, said spacers beingtransversely extended long plate and having a height smaller than thatof said thin fins and a thickness preferably larger than that of saidthin fins; said thin fins being spaced alternately with said spacerswith said first through holes aligned with said second through holes;and said rivets being extended through said aligned first and secondthrough holes to firmly bind said thin fins and said spacers together;and said radiator being ground to remove any unevenness at a bottomthereof; whereby a large number of said thin fins may be included insaid radiator to provide largely increased contacting surfaces with airand accordingly ensure quick radiating of heat produced by a workingelement, such as a chip in a computer, and whereby said radiator may beeconomically produced to have different dimensions simply bycorrespondingly increasing numbers of said thin fins and said spacerswithout the need of cutting more dies.
 2. A radiator with thin fins asclaimed in claim 3, wherein said metal sheets for forming said thin finsand said spacers may be aluminum or copper that has high coefficient ofheat transmission.
 3. A radiator with thin fins as claimed in claim 3,wherein two outmost ones of said a plurality of thin fins are providedon a top edge at predetermined positions with outward extended ears towhich a radiator fan may be fastened to enable said radiator to provideenhanced radiating effect.